The Unique Problem of Inventions Which Are Fully Enabled and Fully Described, But Not Fully Understood (Merrell Dow's Terfenadine Revisited) H. Samuel Frost of Bereskin & Parr 2007 Intellectual Property Journal October 2007 © Bereskin & Parr Bereskin & Parr 40 King Street West, 40th Floor, Toronto, Ontario, Canada M5H 3Y2 Phone: 416-364-7311 Fax: 416-361-1398 www.bereskinparr.com 1 Introduction ...........................................................................................................3 Inventions That are Not Fully Understood.........................................................3 Public Right to Use an Invention ...........................................................................4 Prior User Right.................................................................................................5 Novelty Requirement.........................................................................................6 Requirement for Fully Enabling Disclosure........................................................7 Patent Term.......................................................................................................8 Public Right to Use an Expired Invention ..........................................................8 The Dual Role of the Novelty Standard...............................................................10 Merrell Dow (Terfenadine) Case .........................................................................11 Germany..........................................................................................................11 The United States............................................................................................12 The United Kingdom........................................................................................13 Anticipation by Use ......................................................................................13 Anticipation by Disclosure............................................................................14 Summary of the Merrell Dow Decisions...........................................................15 Theoretical Variations of the Fact Situation in the Merrell Dow Cases................16 First and Second Patentees are Different Entities...........................................16 Excessive Elapsed Time Between Filings .......................................................17 Identification of Missing Elements Requires a Novel Technique.....................17 Inadequacies of Present Statutory Provisions.....................................................17 Inherency Doctrine, Reverse Engineering Concepts and the Like ......................18 U.S. Inherency Doctrine ..................................................................................22 Proposed Solution to the Problem.......................................................................27 Conclusion ..........................................................................................................28 2 Introduction For the vast majority of patentable inventions, the invention is fully understood, so that a disclosure in a patent specification, meeting common requirements for a complete and enabling written description, necessarily discloses all the information necessary to carry out the invention. Once any patent rights have expired, then this information is in the public domain and the public are free to use the invention. However, many patent systems recognize that patent law is not concerned with scientific understanding of technology, but rather is concerned with inventions that have practical and commercial utility and that can be described in sufficient detail to be carried out. Thus, many patent systems do not require an inventor to have full knowledge of the science and technology behind the invention, but merely be in possession of sufficient information to describe the invention and to enable others skilled in the field to carry out the invention. For some inventions, this necessarily results in the patent specification for the invention being 'incomplete' and missing some element of understanding. In many cases, the missing element may be no more than a pure scientific discovery or principle, that may be meritorious in a scientific sense but that may not be suitable subject matter for patent protection. There are, however, a set of such inventions where a missing element may be patentable in its own right, and more importantly, in a smaller subset, such patent protection in a secondary patent can circumscribe or limit use of the invention disclosed in the primary patent. For this small subset, an analysis of judicial decisions shows that, in most jurisdictions, courts really only have two effective options: (1) refuse to recognize protection for any secondary patent on the missing element, so as to prevent apparent recapturing of subject matter already covered in the primary patent; or (2) find claims in the secondary patent of the missing element valid and enforceable, which can affect the right to practice an invention disclosed in the primary patent. The current legal framework therefore provides two drastically different options, and no option for any middle ground. In addition to not providing any middle ground between these two options, it will also be argued that there are two separate but corresponding public policy issues that are not often identified, namely that when a patent expires the public should be free to use the invention and also that the patent system should provide an incentive to inventors to improve the understanding of incomplete inventions and to discover any such missing element. 3 It will be argued that, for the small but important subset of inventions, it is necessary to find a balance or some middle ground between these two public policy issues. It will be further argued that, most patent laws are, surprisingly, silent on the issue of any general or public right to use an invention in the public domain, and after expiry of any patent rights. Consequently, defining such a middle ground can only be achieved by inclusion of a new provision providing such a public right to use of an invention, a provision that, to the author's knowledge, is not found in any current patent laws. This paper addresses general principles, rather than reviewing the law of any country in detail, and reference will be made to decisions from Canada, U.S. and Europe. Inventions that are Not Fully Understood Patent laws in many countries recognize that a complete and enabling disclosure need only be complete in a practical or utilitarian sense. That is, the disclosure must contain sufficient information to enable a skilled person to carry out the invention. More specifically, there is no requirement that an inventor be in possession of a full understanding and explanation of the physical or chemical process, or other science, behind the invention. This merely underscores the fact that patent law is concerned with the useful and practical arts, and is not, fundamentally, concerned with pure science. Such a full understanding and its disclosure are here labeled a "scientific disclosure" to contrast it with an "enabling disclosure". In many cases these will be one and the same. However, as noted in the introduction there can be significant cases where the difference or missing element between these two types of disclosure amounts to more than just a scientific explanation and may amount to subject matter that is patentable separately. Indeed, one can argue that an inventor can never, with complete certainty, assert that a full "scientific disclosure" has been made, since we can never delimit what we do not understand. For example, before the concepts of atoms and molecular structure were developed, early chemists could detail "enabling" instructions to mix certain starting ingredients under certain conditions to yield a useful end compound - the inventor, at the time, could only have provided a disclosure entirely silent on details of the chemical reactions occurring, but could have honestly believed that it was a complete "scientific disclosure". Such inventions will often arise in pharmaceutical and biotechnology related inventions, since chemical and biological processes taking place in living organisms are complex and often not amenable to easy analysis. 4 Thus, while patent laws only require an "enabling disclosure", practice of the invention necessarily, even if unknowingly, requires using the full "scientific disclosure". Public Right to Use an Invention It is fundamental to any patent system with a limited term that, once a patent is expired, the public should be free to use the invention and the invention should not be subject to or limited by any later granted patent rights. The public's right to use an expired patent, or more generally any old technology in the public domain, is not commonly defined, and is usually implicit in provisions limiting patent term and determining patent expiry dates. It is submitted here that an important corollary to the requirement for a full and enabling disclosure is that, it is only this disclosure that ensures the public has unfettered use of the invention after expiry of an initial patent for the invention. Put another way, if any later applicant attempts to craft claims covering the subject matter of an earlier patent, provided the earlier patent does indeed have a complete and enabling disclosure, it will destroy the novelty of such later claims. Prior User Rights Patent laws usually are confined to defining the rights